/******************************************************************************
 * Top contributors (to current version):
 *   Morgan Deters, Tim King
 *
 * This file is part of the cvc5 project.
 *
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
 * in the top-level source directory and their institutional affiliations.
 * All rights reserved.  See the file COPYING in the top-level source
 * directory for licensing information.
 * ****************************************************************************
 *
 * Simple, commonly-used routines for Boolean simplification.
 */

#include "smt_util/boolean_simplification.h"

namespace cvc5 {

bool BooleanSimplification::push_back_associative_commute_recursive(
    Node n, std::vector<Node>& buffer, Kind k, Kind notK, bool negateNode)
{
  Node::iterator i = n.begin(), end = n.end();
  for(; i != end; ++i){
    Node child = *i;
    if(child.getKind() == k){
      if(! push_back_associative_commute_recursive(child, buffer, k, notK, negateNode)) {
        return false;
      }
    }else if(child.getKind() == kind::NOT && child[0].getKind() == notK){
      if(! push_back_associative_commute_recursive(child[0], buffer, notK, k, !negateNode)) {
        return false;
      }
    }else{
      if(negateNode){
        if(child.isConst()) {
          if((k == kind::AND && child.getConst<bool>()) ||
             (k == kind::OR && !child.getConst<bool>())) {
            buffer.clear();
            buffer.push_back(negate(child));
            return false;
          }
        } else {
          buffer.push_back(negate(child));
        }
      }else{
        if(child.isConst()) {
          if((k == kind::OR && child.getConst<bool>()) ||
             (k == kind::AND && !child.getConst<bool>())) {
            buffer.clear();
            buffer.push_back(child);
            return false;
          }
        } else {
          buffer.push_back(child);
        }
      }
    }
  }
  return true;
}/* BooleanSimplification::push_back_associative_commute_recursive() */

}  // namespace cvc5